Re: [PATCH v2 00/14] list: Prepare entry iterators to cache cursor state

Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/[email protected]> Tue, 9 Jun 2026 10:05:58 +0300
Newsgroups gmane.linux.ports.tegra,gmane.linux.kernel.drbd.devel,gmane.linux.block,gmane.linux.kernel.firewire.devel,gmane.comp.video.dri.devel,gmane.comp.freedesktop.xorg.drivers.intel,gmane.linux.kernel.spi.devel,gmane.linux.ports.arm.kernel,gmane.linux.sound,gmane.linux.kernel
Organization Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo
Message-ID <[email protected]>
On Tue, Jun 09, 2026 at 09:47:34AM +0300, Andy Shevchenko wrote:
> On Tue, Jun 09, 2026 at 02:13:33PM +0800, Kaitao Cheng wrote:
> > 
> > This series prepares for, and then updates, the list_for_each_entry()
> > family so the common entry iterators cache their next or previous cursor
> > before the loop body runs.

While code looks okay, this doesn't explain "why?" aspects.

> > The first 13 patches open-code loops that intentionally depend on the
> > old "derive the next entry from the current cursor at the end of the
> > iteration" behaviour.  These loops append work to the list being walked,
> > restart traversal after dropping a lock, skip an entry consumed by the
> > current iteration, or otherwise adjust the cursor in the loop body.
> > 
> > The final patch changes include/linux/list.h to keep a private cursor in
> > the common entry iterators while preserving the public macro interface.
> > The safe variants remain available when callers need the temporary
> > cursor explicitly or have stronger mutation requirements.
> 
> Something is really wrong with the patch series email chaining.
> Patches 3, 10, and 13 start the subthreads. Please, check your
> tools and fix them accordingly.
> 
> Note, `git format-patch ...` should not have this "side-effect"
> when used correctly.

-- 
With Best Regards,
Andy Shevchenko